1. Field of the Invention
The present invention relates to a semiconductor integrated circuit, and more particularly, to a temperature detection circuit insensitive to a supply voltage and temperature variation.
2. Description of the Related Art
Various manufacturing processes implement temperature monitoring for process control. In addition, micro-controllers or microprocessors use methods of measuring temperature in digital format. Integrated circuits (IC) typically do not use external components for measuring temperature, but directly read out temperature digitally. Such an IC temperature detector may be embedded in another integrated circuit.
Typically, an IC has a predetermined operational temperature range, outside of which errors, including device failure, can occur. To ensure that the IC does not operate outside the predetermined operational temperature range, a temperature detector is disposed inside the IC. If the temperature of the IC exceeds a predetermined temperature, the temperature detector makes the IC stop its operation so as to prevent an occurrence of data error and reliability problems. However, the conventional temperature detection circuits are generally sensitive to a supply voltage and semiconductor process variation.
Accordingly, there is a need for a temperature detection circuit that is insensitive to a supply voltage variation and temperature variation.